So far, the US produces more electricity from geothermal energy than does any other country. Four states have geothermal power plants California has the most, followed by Nevada, Utah and Hawaii – and more are planned in these states and in Idaho. The US Department of Energy’s “Geo-Powering the West” program seeks to expand the use of geothermal resources in 19 western states.
US plant types vary widely. One little 300kW geothermal powerhouse in northern California runs all by itself and automatically radios an operator when it needs maintenance. At one of Nevada’s geothermal plants, the heat from geothermal water is used to dry onions and garlic before it is injected back into the reservoir. Hawaii’s geothermal plants provide over 20 percent of the electricity used on the Big Island. And the world’s largest single geothermal power plant, 185MW, is nearing construction near southern California’s Salton Sea.
The Philippines and Indonesia have an abundant geothermal resources. Geothermal generates about one-fourth of the electricity in the Philippines, making this country the second largest user of geothermal electricity in the world (after the US). Italy was the site of the first geothermal power development. Its beautiful dry steam field of Larderello, developed in 1904, is still generating electricity today. Other places with large geothermal power developments include Mexico, Iceland, New Zealand, Japan and several Central American countries.